S.M. Safavi - Electerical Engineering, Amirkabir University of Technology
M.H. Yaghmae - Computer Engineering, Ferdowsi University of Mashhad

Differentiated Services (Diffserv) which was proposed by Internet Engineering Task Force (IETF), is a scalable and robust model for providing the end-to-end QoS. In the Diffserv networks, metering mechanisms are used to measure traffic stream. The single rate Three Color Meter (srTCM) [۱],which was proposed by IETF, meters an IP packet stream and marks its packets either green, yellow, or red. Marking is based on a Committed Information Rate (CIR) and two associated burst sizes, a Committed Burst Size (CBS) and an Excess Burst Size (EBS). In this paper, a Fuzzy Logic Controller (FLC) is proposed which can be used as a metering/marking mechanism in the Diffserv’s routers. Simulation results show that the proposed FLC based mechanism has better QoS performance and higher utilization than traditional srTCM mechanism.

QoS, Differentiated Services, Metering, marking, Fuzzy logic